Texas Instruments TravelMate 5000 Series, Maintenance Manual

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1.8.12.1 AC Power Adapter
The computer is equipped with a universal AC power adapter that converts
AC voltage (100 to 240 VAC, 50 to 60 Hz) into DC voltage used to operate
the notebook and charge the batteries. The adapter also supplies sufficient
power to drive an attached EZ-Dock or EZ-Dock Plus Port Replicator option
that may be attached to the notebook.
1.8.12.2 Intelligent Battery Packs
The TM5000 Series Notebooks hold up to two intelligent battery packs
(Lithium-Ion) as shown in Figure 1-4. Each intelligent battery pack contains
circuitry to monitor the charge remaining in the pack and recharge the pack
when the AC Adapter is present.
The rechargeable battery packs provide DC power for the computer (and for
the NVRAM and real time clock battery on the Main Board) when the AC
Adapter is not being used.
Each battery pack contain four LEDs to display charge status of the pack
(either when the Display Charge Status button is pressed on the front of the
battery pack or when the batteries are being charged). The four LEDs
indicate the percent of charge on the batteries as shown in Figure 1-4.
As long as one battery pack has sufficient charge (25% or more) to operate
the system, the remaining battery pack may be removed with the notebook
operational (in Standby mode).
To remove a battery pack from the notebook while the notebook is powered
off, press the
Battery Eject Button (just above the top left side of the
keyboard) and remove the pack from the front of the notebook. If the
batteries are not totally discharged, you can replace a battery pack with the
system operational (in
Suspend Mode ) without loosing data. Insert a
charged pack back into the system. Repeat the procedure with the
remaining pack if you have a second replacement battery.
1.8.12.3 NVRAM Battery
The Main Board in the notebook is equipped with a smaller 3.6V, 11 MAH
(milli amphere hours) Nickel Metal Hydride battery which drives the battery
powered CMOS memory (non-volatile memory) and real time clock when the
main batteries are out of the notebook. The NVRAM battery is recharged
from the Vcc supply when the notebook is operating off battery power or
from the AC adapter when attached even if the notebook is powered off.
1.8.12.4 Power Supply Section of Main Board
The Power Supply Section receives approximately 7.2 VDC from the battery
packs and uses this input voltage to ge3, +5 and +12 regulated
output voltages to provide power for all internal notebook board assemblies.
The output of the +5 volt regulator also drives the LCD inverter circuit on
the Inverter Board Assembly (part of the Cover-Display Assembly)..
General Description 1-39